1. Field of the Invention
The present invention relates to a dosing feeder for preferably small amounts of liquid which, when in contact with skin or eyes, may cause injuries, e.g., in medical treatment and dental care, particularly bonding liquid for mending or filling of cavities with UV-light hardening plastic materials.
2. The Prior Art
In dosing preferably small amounts of liquid which, when in contact with skin or eyes, may cause injuries, e.g., in medical treatment and dental care, protective equipment is required that often is difficult to use, e.g., plastic gloves and safety goggles, in order to prevent injuries in the event the aggressive liquid splashes, above all in connection with the dosing itself, but also to prevent skin contact with dosing equipment such as pipettes and dropping bottles that are wetted on the outside by the liquid concerned. A typical liquid of that sort is the liquid used in dental care as bonding liquid when mending or filling cavities with UV-light hardening plastic materials. It is very difficult for the treating dentist to protect himself from skin contact with the bonding liquid as a number of treatment steps are going on simultaneously and cannot be interrupted, e.g., in order to put on or to change protective gloves. At the same time, it is very expensive to have personnel with protective equipment available to handle the dosing and serve the attending dentist.
The object of the present invention is to provide a dosing feeder for injurious liquids that avoids the above-mentioned disadvantages with special protective equipment.
The object is achieved with a dosing feeder that includes a dosing arm that includes at least one dosing cup which is open at the top and arranged in a corresponding opening in a dosing head that in its turn includes a first duct in connection with the container. The dosing head is movable or turnable in relation to the dosing arm so that the dosing cup alternately may be brought in connection with the first duct for the feed of liquid or may release the dosing cup so that it becomes accessible for the liquid. The dosing head may alternately be constructed to include two or more dosing cups of different sizes and on filling, the desired cup is chosen by a linear movement of the dosing head and that cup is made accessible by either a further linear movement or a rotation of the dosing head.
In a practical embodiment a linearly movable dosing head may then have the liquid container fixed on the upper side, but also a liquid container that is stationary fixed, e.g. on a stand and that is connected with the first duct via a flexible hose.
Preferably also a second duct is arranged in the dosing head and accessible from above and admits accessibility to the dosing cup when the first duct to the liquid container is brought out of connection with the same.
In a preferred embodiment the dosing arm is cylinder-shaped, the dosing head being turnable around the dosing arm. The first duct is on one side of the dosing arm and the second duct is on the other side of the dosing arm, both ducts showing mainly the same direction of extension. When filling liquid into the dosing cup, the container is above the dosing arm and the first duct is connected with the dosing cup. The container is in position of rest under the dosing arm, the second duct being connected with the dosing cup. Also in this embodiment the dosing arm may show two or more dosing cups, where the desired dosing cup is chosen by a linear movement of the dosing head.
Further features and characteristics concerning the present invention will become evident from the description of the attached drawings.